Electrical apparatus



Nov. 20, 1923.

D. CONLAN, JR

ELECTRICAL APPARATUS Original Filed Dec. 24, 1920 INVENTOR DAVID CON LAN JR.

BY I W20 '1 ATTORNEY Patented Nov. 20, 1923.

* .iJNITE STATES PATENT orrica.

navn) CONLAN, .13., or BROOKLYN, NEW YORK, nssrcnon T HAR'VEY HUIBBELL, mo,

A CORPORATION OF CONNECTICUT.

lirncrmon. nrranarusc 1 Original-application filed ilecember To all whom it may concern:

Beit known that I, DAVID CONLAN, Jr.,

a citiien of the United States, and a resldent of Brooklyn, Kings County,.and State of New York, have invented certain new and useful Improvements in Electrical Apparatus, of which the following is acspecr fication. I

This invention relates to circuit extension devices on the Order of those disclosed in Patent 1,363,394 and in my'co-pending ap plication, Serial No. 432,983, the present applicationbeing a division from the application referred to.

In my prior inventions, branch circuits are supplied by cords entered through the sides of special attachment plugs designed so that they may be connected end-on-end to an indefinite number.

One of'the objects of this invention is to improve on that construction and particularly a as regards the separation of the various units so as to make it possible for a pull on the extension cord or cords to'effect the 95 uncoupling of the units.

' Other objects are to provide a simple and practical strain relief for the outlet cord and to protect and support the angularly ex-' tending portion of the cord where it leaves 3" the side of the plug structure.

{ These and other objects are attained in my invention by means of certain novel features of construction, combination, ar-

rangement and relation of parts, as will appear from the following specificatlon, which should be rhadin'conjunction with'the accompanying drawing wherein I have illustrated the invention embodied in one of its simplest and most practical forms. 4 Figure 1 in the drawing referred to is a perspective view-showing several of the in- 4 terchangeable plug units inseparated relation and illustrating how one may be plugged onto the end of the other for the purpose of extending a circuit and providingzadditional branches therefromigure 2 is an end view of one of' the plug members.

Figures 3 and 4 are vertical or longitudinal sectional views of "two of the units in assembled relation, these views being taken on substantially the planes of lines 3-3 and 4-4 respectively of -Fi re 2. a

In Figure 1 I have in icated at 5 the face 2 4, 1920, Serial No. 432,983. Divided and this Serial NO. 477,003.

application filed June Of a baseboard, wall or other Outlet fixture having a pair of the usual contact clips 6 for engagement by the blades of an ordinary attachment plug. I have also indicated in this view one of my special attachment plugs at 7 ready .for engagement with the Outlet fixture, a second attachment plug at 8 ready to be plugged into the first attachment plug and an end attachment plug at 9 ready to be coupled to the second plug. Each one of these plugs consists of an insulating base 10' plugs, such as those 1 plugs. These circuitextending contacts are shown at 13 in Figures 3 and 4 as housed in insulating sockets 14 in the lower or outer ends of the plug bases, which sockets, for simplicity of manufacture, may extend entirely through the bases from end to end thereof, substantially as illustrated.

The through-circuit plugs (7 and8) are provided with cord outlets in the form of passages 15 extending entirely through the base of each plug from the binding posts at the upper end thereof, out through the bottom thereof so that in each instance the cord or extension circuit conductor 16 emerges from the bottom of the plug to which it is attached. Clearance for this emerging portion of the cord is provided at the meeting ends of abutting plugs by means of notches or recesses 17 formed in the upper edge portions of the plugs in position to lineup with the cord outlets in the ends of preceding plugs.

' a The longitudinal cord passages 15 extending as they do substantially at right angles to the bases of the terminal blades, make a sharp turn for the cords at the binding posts and hence rovide an efficient form of strain relief, and this strain relief may be made more effective by. providing an en- 'largement in the upper end of the cord Outlet passage, such as I have indicated at 18, to

receive a knot tied in the conductor cord, as

shown at 19 in Figure 3.

lVith this improved construction it will be seen that the cord is led off from the plug structure at an easy or gradualincline and that, as shown in Figure 3, the bent or angular part of the conductoris housed and protected from chafing, etc. Also it will be evident that by reason of the fact that the cord emerges directly from the end of the plug, it is effectiveto apply an endwise pull to the plug and this makes it ossible "for the units to be separated by simp y pulling endwise on any one of the cords. This, therefore, provides an easy means for quickly uncoupling 'the plugs in case of a sudden necessity and alsoalfords a certain amount of protection for the cords so that in case of a heavy strain on the cords, the plugs will be pulled apart before the cords will break. This overcomes to a large extent the dangers arising from short-circuiting, which otherwise might result fromapplication of excessive force to the extensionrcords.

What I claim is:

f 1. In electrical apparatus of the character" described, an attachment plug for extending a through circuit andiproviding a branch circuit, comprising a cylindrical insulating base, a pair of terminal blades projecting from one end of said base and provided with binding posts at the bases of the same for the nal posts housed in the insulating sockets and electrically connected with the terminal blades.

2. In electrical apparatus of the character described, an attachment plug for extending a projecting through circuit and providing a branch cir:

cuit comprising a cylindrical insulating base having at one end a pair of connectingin contacts and seatedin the opposite end a pair of through-circuit terminals electrically opposite the cord outlet to accommodate the outgoing portion-of a branch circuit cord from a preceding plug unit.

3. In electrical apparatus of the character described, a plurality of separable and interchangeably engageable circuit extension units, each comprising an insulating base having at one end a pair of connecting-in contacts and seated in the opposite end a pair of through-circuit.terminals electrically connected with the connecting-in contacts, said connecting-in contacts having'binding posts and the insulating supporting base having a cord outlet extending longitudinally therethrough from said binding-"posts at one end 0f the base to the opposite end of the base and a notch in the edge thereof positioned'to accommodate the out-going portion of the extension cord from a preceding unit.

4. In electrical apparatus of the character described, a plurality of separable circuit extension units each comprising an insulating base and a pair of projecting terminal blades at one end of the same, one of said insulating bases having insulating sockets in the end thereof opposite the end from which the terminal blades project, terminal posts housed in said sockets and connected with the terminal blades and positioned to be engaged by the projecting blades of a succeeding unit, binding posts for the terminal blades on the first unit, the baseof said first unit having a cord outlet extending from said binding sts out ,through the opposite end of the ase andthe base of the second unit having a notch in the edge thereof in line with the cordoutlet opening in the end of the first unit. I i p In witness whereof, I have hereunto set my hand this. 27th day of Ma 1921.

' 1 DAVID ONLAN,.JR. 

